I have an issue with rand() while fork()ing and using IO::Socket::SSL.

In all forked processes rand() gives me the same set of random numbers. If I call rand() several times I get random numbers as expected, but in all forked processes I get the same random set.

If I remove IO::Socket::SSL the set is random in all processes.

I've reduced the case down to this: 

use strict;
use IO::Socket::SSL;

foreach (1 .. 5) {
  my $pid = fork();
  next if $pid;

  random();
  random();

  exit;
}

sub random {
  print sprintf("Process %d: %d", $$, int(rand(100000))), "\n";
}

[download]

If I run the script I get this output: 

$ perl fork_rand.pl
Process 13788: 32768
Process 13788: 3778
Process 13789: 32768
Process 13789: 3778
Process 13790: 32768
Process 13790: 3778
Process 13791: 32768
Process 13791: 3778
Process 13792: 32768
Process 13792: 3778

[download]

I would expect the numbers to be random in all processes -- not return the same set of numbers.

If I remove IO::Socket::SSL everything works as expected: 

$ perl fork_rand.pl
Process 13806: 94050
Process 13806: 14790
Process 13807: 89099
Process 13807: 93200
Process 13808: 48447
Process 13808: 14001
Process 13809: 28378
Process 13809: 71603
Process 13810: 44245
Process 13810: 86800

[download]

Is this a known bug?

I've tested on both Linux and FreeBSD, with latest version of IO::Socket::SSL and Perl 5.8.8.

In reply to fork(), IO::Socket::SSL and rand() by digmon

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